Filmed observations of spontaneous interactions between mothers and their newborn infants (N = 50) were used to quantify the occurrences, duration and frequency of maternal tactile behaviours (stroking, kissing, touching the clothes, etc.). The analysis of the data shows that these maternal behaviours vary from one mother to another according to the activities of the newborn infant (sleeping, arousal but not feeding, feeding) and to different biological (sex of the infant, birthweight) and social (socio-economic status of the mother) variables. These results would suggest discussion topics concerning the differences between the mother-infant interaction systems.